1. Field of the Invention
The present invention relates to a paper-making machine, and, more particularly, to a support for a drying cylinder bearing in a paper-making machine.
2. Description of the Related Art
A paper-making machine may be thought of as including various portions or sections along the running direction of the paper web through the machine. For example, the paper-making machine may include a wet end, a forming section, a press section and a dryer section. The dryer section receives a higher moisture content paper web and drys the paper web to a desired lower moisture content. The dryer section includes a plurality of heated drying cylinders which respectively engage and carry the paper web from the upstream end of the dryer section to the downstream end of the dryer section.
In order to heat up certain drying cylinders within such a dryer section of a paper-making machine, it is known to attach steam carrying pipes to these cylinders. Since the cylinders expand upon heating in all directions, especially along their longitudinal direction, i.e., along the axis about which the cylinder rotates in service, it is known to incorporate at least one bearing which rotatably carries the drying cylinder and provides room for some relative axial movement between the inner and outer races. The room for relative movement can compensate for the thermal expansion of the drying cylinder during operation. Thermal expansions along the longitudinal axis about which the cylinder rotates are accommodated by the bearing so that the fixed structure to which the drying cylinder is mounted will not be moved or deformed during operation. A problem is that such freely carrying bearings may require more frequent replacement than standard bearings because of the added wear caused by the axial movement. Another problem is that such freely carrying bearings are more expensive than standard bearings.